Improving the promise of embedded pragmatic trials: Surmountable barriers encountered in an evaluation of home-based HPV self-sampling to increase cervical cancer screening in overdue women.

Despite increased attention on how to conduct pragmatic trials and their importance, there remains an under-appreciation for the reality of what they take to design, compete and secure funding and execute. Many barriers are surmountable through increased exposure to experiences from completed trials. This report summarizes our experience in designing, securing funding and implementing the Home-Based Options to Make screening Easier (HOME) pragmatic trial, which was designed to evaluate home human papillomavirus testing for cervical cancer screening in underscreened women (women who had not received a cervical cancer screening test in ≥3.5 years). This report highlights factors at the level of research teams, organizations seeking to conduct embedded research, reviewers and funding agencies that challenge pragmatic trial design and execution. There is an urgent need to train on peer-reviewers how to evaluate embedded trial grant proposals, for agencies to pursue more rapid and innovative funding strategies, and to consider strategies for reviewers and funders to evaluate stakeholder buy-in (beyond letters of support). These factors together are needed to realize the promise of pragmatic trials to more efficiently and effectively generate critical data that inform changes in health care delivery and benefit patients.

The niche of an invasive marine microbe in a subtropical freshwater impoundment.

Growing attention in aquatic ecology is focusing on biogeographic patterns in microorganisms and whether these potential patterns can be explained within the framework of general ecology. The long-standing microbiologist's credo 'Everything is everywhere, but, the environment selects' suggests that dispersal is not limiting for microbes, but that the environment is the primary determining factor in microbial community composition. Advances in molecular techniques have provided new evidence that biogeographic patterns exist in microbes and that dispersal limitation may actually have an important role, yet more recent study using extremely deep sequencing predicts that indeed everything is everywhere. Using a long-term field study of the 'invasive' marine haptophyte Prymnesium parvum, we characterize the environmental niche of P. parvum in a subtropical impoundment in the southern United States. Our analysis contributes to a growing body of evidence that indicates a primary role for environmental conditions, but not dispersal, in the lake-wide abundances and seasonal bloom patterns in this globally important microbe.

The immune response and maternal antibody interference to a heterologous H1N1 swine influenza virus infection following vaccination.

This study investigated the efficacy of a bivalent swine influenza virus (SIV) vaccine in piglets challenged with a heterologous H1N1 SIV isolate. The ability of maternally derived antibodies (MDA) to provide protection against a heterologous challenge and the impact MDA have on vaccine efficacy were also evaluated. Forty-eight MDA(+) pigs and 48 MDA(-) pigs were assigned to 8 different groups. Vaccinated pigs received two doses of a bivalent SIV vaccine at 3 and 5 weeks of age. The infected pigs were challenged at 7 weeks of age with an H1N1 SIV strain heterologous to the H1N1 vaccine strain. Clinical signs, rectal temperature, macroscopic and microscopic lesions, virus excretion, serum and local antibody responses, and influenza-specific T-cell responses were measured. The bivalent SIV vaccine induced a high serum hemagglutination-inhibition (HI) antibody titer against the vaccine virus, but antibodies cross-reacted at a lower level to the challenge virus. This study determined that low serum HI antibodies to a challenge virus induced by vaccination with a heterologous virus provided protection demonstrated by clinical protection and reduced pneumonia and viral excretion. The vaccine was able to prime the local SIV-specific antibody response in the lower respiratory tract as well as inducing a systemic SIV-specific memory T-cell response. MDA alone were capable of suppressing fever subsequent to infection, but other parameters showed reduced protection against infection compared to vaccination. The presence of MDA at vaccination negatively impacted vaccine efficacy as fever and clinical signs were prolonged, and unexpectedly, SIV-induced pneumonia was increased compared to pigs vaccinated in the absence of MDA. MDA also suppressed the serum antibody response and the induction of SIV-specific memory T-cells following vaccination. The results of this study question the effectiveness of the current practice of generating increased MDA levels through sow vaccination in protecting piglets against disease.

A simple generic infection model for foliar fungal plant pathogens.

ABSTRACT In this study, a simple generic infection model was developed for predicting infection periods by fungal foliar pathogens. The model is designed primarily for use in forecasting pathogens that do not have extensive epidemiological data. Most existing infection models require a background epidemiological data set, usually including laboratory estimates of infection at multiple temperature and wetness combinations. The model developed in this study can use inputs based on subjective estimates of the cardinal temperatures and the wetness duration requirement. These inputs are available for many pathogens or may be estimated from related pathogens. The model uses a temperature response function which is scaled to the minimum and optimum values of the surface wetness duration requirement. The minimum wetness duration requirement (W(min)) is the number of hours required to produce 20% disease incidence or 5% disease severity on inoculated plant parts at a given temperature. The model was validated with published data from 53 controlled laboratory studies, each with at least four combinations of temperature and wetness. Validation yielded an average correlation coefficient of 0.83 and a root mean square error of 4.9 h, but there was uncertainty about the value of the input parameters for some pathogens. The value of W(min) varied from 1 to 48 h and was relatively uniform for species in the genera Cercospora, Alternaria, and Puccinia but less so for species of Phytophthora, Venturia, and Colletotrichum. Operationally, infection models may use hourly or daily weather inputs. In the case of the former, information also is required to estimate the critical dry-period interruption value, defined as the duration of a dry period at relative humidities <95% that will result in a 50% reduction in disease compared with a continuous wetness period. Pathogens were classified into three groups based on their critical dry-period interruption value. The infection model is being used to create risk maps of exotic pests for the U.S. Department of Agriculture's Animal Plant Health and Inspection Service.

A role for biliverdin IXalpha in dorsal axis development of Xenopus laevis embryos.

The determinants of Xenopus laevis embryos that act before their first cell division are mandatory for the formation of mRNas required to establish the dorsal axis. Although their chemical identities are unknown, a number of their properties have long been recognized. One of the determinants is present in the cytoplasm and is sensitive to UV light. Thus, exposing stage 1 embryos to either standard 254-nm or, as shown here, to 366-nm UV light during the 0.3-0.4 time fraction of their first cycle inactivates the cytoplasmic determinant. As a consequence, both types of irradiated embryos fail to express dorsal markers, e.g., goosecoid and chordin, without affecting formation of ventral markers, e.g., Vent-1. The developmental outcome is dorsal axis-deficient morphology. We report here that biliverdin IXalpha, a normal constituent of cytoplasmic yolk platelets, is photo-transformed by irradiation with either 254- or 366-nm UV light and that the transformation triggers the dorsal axis deficiency. When the 254- or 366-nm UV-irradiated embryos, fated to dorsal axis deficiency, are incubated solely with microM amounts of biliverdin, they recover and form the axis. In contrast, incubation with either in vitro photo-transformed biliverdin or biliverdin IXalpha dimethyl ester does not induce recovery. The results define an approach to produce dorsal axis-deficient embryos by photo-transforming its biliverdin by irradiation with 366-nm UV light and identify an unsuspected role for biliverdin IXalpha in X. laevis embryogenesis.

The French prescription for health care reform.

In 1996, the French government introduced a wide-ranging health care reform which aimed to resolve the problems of rising health expenditure and a levelling off in health sector income. Changes in the regulation of the health care system sought to strengthen quality while improving professional practice. At the same time the changes were intended to encourage greater synergy both between professionals and between the different parts of the system, thus promoting greater cost-effectiveness. The tools designed to achieve these results included: the creation of new regional hospital agencies, the introduction of cash-limited budgets at national and regional level, the launching of a contracting procedure between health authorities and hospitals and the setting up of a new health care accreditation agency. With some signs of improvement in the overall health insurance budgetary situation, the Jospin government seems to be supporting the broad lines of the reform introduced by its predecessor.

Inventory of validation approaches in selected health telematics projects.

This paper presents the results from an inventory of validation approaches and methodologies which have been used in selected health telematics projects. The inventory was performed in the VATAM Validation of Telematic Applications in Medicine project, HC1115HC. The purpose of the inventory was to analyse the methodologies and their application assumptions in order to identify possibilities for harmonization and consolidation. The inventory was performed using five validation dimensions: IT-development; quality; user; technology assessment and marketing. The inventory results show that possibilities exist to synthesise methodologies and to provide practical guidance and support for projects that are developing health telematics applications. All stakeholders in health telematics projects, i.e. users, health care decision-makers, developers, suppliers and IT-industries, can benefit from practical validation guidelines and support for validation when guidelines are represented in a usable, easy to access and informative way.

The VATAM guidelines.

Evaluation and assessment of the impact of information and communication technology in medicine is gaining interest. Unfortunately, till now there were no agreed upon approaches. The objective of the VATAM project is to develop guidelines that will assist assessors to set-up and execute studies. This paper describes the background of the VATAM project and provides an account of the current state of the guidelines. It concludes with an indication of the developments that will take place in the short term to further elaborate the guidelines and some considerations for consolidation of VATAM's results.

Comparison of articulate brachiopod nuclear and mitochondrial gene trees leads to a clade-based redefinition of protostomes (Protostomozoa) and deuterostomes (Deuterostomozoa)

Nuclear and mtDNA sequences from selected short-looped terebratuloid (terebratulacean) articulate brachiopods yield congruent and genetically independent phylogenetic reconstructions by parsimony, neighbour-joining and maximum likelihood methods, suggesting that both sources of data are reliable guides to brachiopod species phylogeny. The present-day genealogical relationships and geographical distributions of the tested terebratuloid brachiopods are consistent with a tethyan dispersal and subsequent radiation. Concordance of nuclear and mitochondrial gene phylogenies reinforces previous indications that articulate brachiopods, inarticulate brachiopods, phoronids and ectoprocts cluster with other organisms generally regarded as protostomes. Since ontogeny and morphology in brachiopods, ectoprocts and phoronids depart in important respects from those features supposedly diagnostic of protostomes, this demonstrates that the operational definition of protostomy by the usual ontological characters must be misleading or unreliable. New, molecular, operational definitions are proposed to replace the traditional criteria for the recognition of protostomes and deuterostomes, and the clade-based terms 'Protostomoza' and 'Deuterostomozoa' are proposed to replace the existing term 'Protostomia' and 'Deuterostomia'.

VATAM: developing consensus in validation of health telematics applications.

VATAM (Validation of Telematics Applications in Medicine) is an EU supported project in the Health care sector of the Telematics Application Programme. Its objective is to assist other health telematics projects by providing a platform for discussion on validation, eventually resulting in 'guidelines for validation of telematics applications in medicine'. The VATAM work can be subdivided into three phases: the inventory phase (1996) in which information is collected on validation approaches in the Telematics Application Programme, previous efforts and expertise. The dissemination phase (1997) will be used to extend and adapt the framework developed in the inventory phase, through cooperation with other projects The experiences phase (1998) in which the projects are actually applying validation, will be used by VATAM to validate the VATAM methodology. VATAM has finished the inventory phase successfully and is now working on the dissemination phase by--among others--establishing contacts with other projects, and providing information on the inventory through the World Wide Web (URL: http:(/)/www-vatam.unimaas.nl). This paper discusses the approach adopted and the proposed VATAM framework to structure the large variety of validation approaches.

The ACOSTA accompanying measure A2106.

At a time when the informatics and telecommunications industries are looking for new markets to exploit in relation, for example, to the emerging ISDN and broadband communications networks, there is a need to create a broad consensus in Europe by bringing together systematically the relevant industries including telecom service providers, health care providers, insurance organisations, standardisation experts and policy makers. The aim of the ACOSTA (Consensus Formation and Standardisation Promotion) Accompanying Measure is the creation of more general awareness of the relevant environment among all the parties, better specification of common requirements and options taking better account of the real needs of the users, and enlargement of the common market in health care telematics.

Phosphorylation on carboxyl terminus domains of neurofilament proteins in retinal ganglion cell neurons in vivo: influences on regional neurofilament accumulation, interneurofilament spacing, and axon caliber.

The high molecular weight subunits of neurofilaments, NF-H and NF-M, have distinctively long carboxyl-terminal domains that become highly phosphorylated after newly formed neurofilaments enter the axon. We have investigated the functions of this process in normal, unperturbed retinal ganglion cell neurons of mature mice. Using in vivo pulse labeling with [35S]methionine or [32P]orthophosphate and immunocytochemistry with monoclonal antibodies to phosphorylation-dependent neurofilament epitopes, we showed that NF-H and NF-M subunits of transported neurofilaments begin to attain a mature state of phosphorylation within a discrete, very proximal region along optic axons starting 150 microns from the eye. Ultrastructural morphometry of 1,700-2,500 optic axons at each of seven levels proximal or distal to this transition zone demonstrated a threefold expansion of axon caliber at the 150-microns level, which then remained constant distally. The numbers of neurofilaments nearly doubled between the 100- and 150-microns level and further increased a total of threefold by the 1,200-microns level. Microtubule numbers rose only 30-35%. The minimum spacing between neurofilaments also nearly doubled and the average spacing increased from 30 nm to 55 nm. These results show that carboxyl-terminal phosphorylation expands axon caliber by initiating the local accumulation of neurofilaments within axons as well as by increasing the obligatory lateral spacing between neurofilaments. Myelination, which also began at the 150-microns level, may be an important influence on these events because no local neurofilament accumulation or caliber expansion occurred along unmyelinated optic axons. These findings provide evidence that carboxyl-terminal phosphorylation triggers the radial extension of neurofilament sidearms and is a key regulatory influence on neurofilament transport and on the local formation of a stationary but dynamic axonal cytoskeletal network.

Pharmacoepidemiology of bleeding events after use of r-alteplase or streptokinase in acute myocardial infarction.

OBJECTIVE: To determine in nonresearch, general medical practice conditions the comparative incidence and types of bleeding complications after the use of streptokinase (SK) and r-alteplase (recombinant tissue plasminogen activator, rt-PA) to treat acute myocardial infarction (AMI). DESIGN: Retrospective medical record review of concurrently treated patients (96-hour observation posttreatment) in 32 participating hospitals in the US. MAIN OUTCOME MEASURES: The medical record description of all bleeding events regarding the body site affected, changes in hemoglobin concentrations, blood products administered, and clinical outcome (permanent sequelae or death). Bleeding severity was determined by defined criteria. CONTROL DATA: Comorbidity and concomitant medications (e.g., aspirin, heparin, warfarin) likely to predispose or contribute to bleeding events were analyzed. DATA ANALYSIS: Logistic regression analysis. RESULTS: Data from 419 patients who received rt-PA and 207 who received SK were evaluated. In the 96-hour period after initiation of thrombolytic therapy, 30.5 and 31.9 percent of rt-PA and SK patients, respectively, experienced one or more bleeding events (crude risk ratio [CRR] = 1.04; 95 percent confidence interval [CI] 0.91-1.14; p = 0.73). In the first 24-hour period, 21.5 percent of rt-PA and 15.9 percent of SK patients experienced bleeding events (CRR = 0.74; 95 percent CI 0.42-1.15; p = 0.08). The leading types of bleeding and percents of all patients affected were: perivascular access site (18.4 percent), gastrointestinal (6.4 percent), skin/soft tissue/muscle (5.0 percent), urinary (3.4 percent), pulmonary (2.2 percent), systemic (1.9 percent), and oral (1.4 percent). Intracranial bleeding occurred in 4 rt-PA and 2 SK patients; 4 of these patients died. Events deemed clinically significant occurred in 15 rt-PA and 9 SK patients (3.8 percent of all patients). Ten patients likely died from these events, 6 within the first 24 hours. Three rt-PA patients and 1 who received SK (0.6 percent) died of cerebrovascular events within the first 24 hours. After controlling for demographic factors and therapeutic variables, using logistic regression analyses, no thrombolytic-related differences were found in the incidence or severity of bleeding following use of the two thrombolytics. CONCLUSIONS: These clinical data do not support a theoretical advantage of rt-PA to cause less bleeding propensity than SK.

European strategies for training in health information systems.

The Committee of Ministers of the Council of Europe recently adopted a recommendation on training strategies for health information systems. The main elements were: specific adaptation of training both to the wider health care setting and to the individual work situation; training provided on a multidisciplinary basis; involvement of local health care, educational, research and commercial establishments; setting up of a network of reference centres to facilitate rapid exchange and harmonisation at national and European levels.

Increased septic complications with three-drug sequential immunosuppression for cadaver renal transplants.

In 152 renal transplant recipients, the results of immunosuppression with three-drug sequential (Minnesota antilymphocyte globulin, prednisone, azathioprine, and cyclosporine) immunosuppression (n = 107) were compared with those of a two-drug sequential protocol (Minnesota antilymphocyte globulin, prednisone, and cyclosporine) that excluded azathioprine (n = 45). The study groups were comparable by age, sex, etiology of renal failure, incidence of diabetes, and degree of HLA matching. Patient survival at 1 year was not significantly different in the two groups (two drug, 93% versus three drug, 86%; p = 0.19). One-year graft survival was superior in the two-drug group (two drug, 93% versus three drug, 75%; p = 0.02). Analysis of primary transplants only (n = 116) yielded the same results. During the first year, the serum creatinine level remained stable in both groups. As expected, the three-drug therapy group had significantly more bacterial and viral infections. For low-risk primary cadaveric renal transplants, two-drug sequential immunosuppression is superior.

Lysosomal proteinase antigens are prominently localized within senile plaques of Alzheimer's disease: evidence for a neuronal origin.

To investigate the role of proteolysis in amyloid formation, we studied the localization of the proteolytic enzymes, cathepsin D and cathepsin B, in the prefrontal cerebral cortex and hippocampus of human postmortem brains from patients with Alzheimer's disease and from individuals free of neurological disease. In control and Alzheimer brains, cathepsin immunoreactivity within cells was localized to lysosome-related structures, which were particularly abundant in neuronal perikarya. In Alzheimer brain, cathepsin immunoreactivity was also heavily concentrated extracellularly within senile plaques. Cathepsin immunoreactivity associated with plaques was not confined to lysosomes and was distributed throughout the plaque. Isolated amyloid cores, however, were not immunostained. Cathepsin-laden perikarya of degenerating neurons were frequently seen within senile plaques and, in the more advanced stages of degeneration, cathepsin immunoreactivity was present throughout the cytoplasm. Other identified constituents of senile plaques appeared to be less significant sources of cathepsin immunoreactivity, including astrocytes, degenerating neurites, microglia and macrophages. These results demonstrate that lysosomal proteinases are major constituents of the senile plaque and that degenerating neuronal perikarya are a principal source of the cathepsin immunoreactivity. We propose that the unregulated action of extracellular cathepsins liberated from degenerating neurons may lead to abnormal processing of the amyloid precursor protein and to the formation of amyloid locally within senile plaques in Alzheimer's disease.